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K Ibrahim

Publications and source records attributed to K Ibrahim.

At least 19 recordsLinked to original sources
PubMed2006

Identification and properties of steroid-binding proteins in nesting Chelonia mydas plasma.

We report for the first time the presence of a sex steroid-binding protein in the plasma of green sea turtles Chelonia mydas, which provides an insight into reproductive status. A high affinity, low capacity sex hormone steroid-binding protein was identified in nesting C. mydas and its thermal profile was established. In nesting C. mydas testosterone and oestradiol bind at 4 degrees C with high affinity (K (a) = 1.49 +/- 0.09 x 10(9) M(-1); 0.17 +/- 0.02 x 10(7) M(-1)) and low binding capacity (B (max) = 3.24 +/- 0.84 x 10(-5) M; 0.33 +/- 0.06 x 10(-4) M). The binding affinity and capacity of testosterone at 23 and 36 degrees C, respectively were similar to those determined at 4 degrees C. However, oestradiol showed no binding activity at 36 degrees C. With competition studies we showed that oestradiol and oestrone do not compete for binding sites. Furthermore, in nesting C. mydas plasma no high-affinity binding was observed for adrenocortical steroids (cortisol and corticosterone) and progesterone. Our results indicate that in nesting C. mydas plasma temperature has a minimal effect on the high-affinity binding of testosterone to sex steroid-binding protein, however, the high affinity binding of oestradiol to sex steroid-binding protein is abolished at a hypothetically high (36 degrees C) sea/ambient/body temperature. This suggests that at high core body temperatures most of the oestradiol becomes biologically available to the tissues rather than remaining bound to a high-affinity carrier.

Animals↗
PubMed2005

The use of denial in an ethnically diverse British cancer population: a cross-sectional study.

A total of 82 Asian and 117 randomly selected white Caucasian patients at the Leicestershire Cancer Centre were assessed using measures of coping and adaption to cancer. On the Mental Adjustment to Cancer (MAC) scale, Asian patients were more fatalistic (P < 0.0001) and had more significant hopeless/helpless scores (P = 0.007). The two ethnic groups answered the three questions thought to assess denial differently. Caucasians were more likely not to dwell on their illness (73 vs 55.5%, P < 0.0001) and agree with the statement 'I have difficulty believing this is happening to me' (73 vs 60.5%, P < 0.0001). However, Asian patients were more likely to agree with the statement 'I don't really believe I have cancer' (48.2 vs 31.3%, P = 0.019). Within both groups there was an association with denial and anxious preoccupation (P < 0.001). On the Hospital Anxiety and Depression (HAD) scale, there was no difference in anxiety scores between either sexes or between the Asian and Caucasian groups. However, Asian patients were more depressed (P = 0.001). Although denial was significantly related to the presence of both depression (P < 0.0001) and anxiety (P = 0.001) in the entire patient population, there were different predictors of denial in each subgroup. On multiple regression analysis depression was linked with denial in Caucasians, whereas Fighting Spirit (minus helplessness/hopelessness) was linked with denial in Asian patients. There are definite differences in coping styles in British cancer patients according to ethnicity. While significant numbers in both groups employ denial in some form, Caucasian patients appear to adapt to the psychological pressures of cancer more successfully than Asian patients at a particular point in time. Further work is required to elucidate longitudinal relationships between denial and adaption to cancer.

Adaptation, Psychological↗
PubMed2005

Distribution of the molecular forms of Anopheles gambiae and pyrethroid knock down resistance gene in Nigeria.

We investigated the distribution of the molecular M and S forms of Anopheles gambiae and the knock down resistance (kdr) gene associated with pyrethroid and DDT resistance in A. gambiae s.s. at 13 localities across Nigeria. Two-three days old adult female mosquito reared from larval collections were tested using standard WHO procedures, diagnostic test kits and impregnated papers to assess their pyrethroid resistance status. Specimens were identified by PCR assays and characterized for the kdr gene. DNA from adult A. gambiae s.s. collected from human dwellings were also tested for the presence of the kdr gene. The overall collection was a mix of the molecular M and S forms across the mangrove (63:37%), forest (56:44%), and transitional (36:64%) ecotypes, but almost a pure collection of the S form in the Guinea and Sudan-savanna. Results of insecticide susceptibility tests showed that mosquitoes sampled at seven localities were susceptible to permethrin, deltamethrin, and DDT, but populations of A. gambiae resistant to these insecticides were recorded at six other localities mainly in the transitional and Guinea-savanna ecotypes. The kdr gene was found only in the molecular S forms, including areas where both forms were sympatric. The overall kdr frequency was low: <47% in forest, 37-48% in the transitional, and 45-53% in Guinea-savanna. The data suggest that pyrethroid resistance in A. gambiae in Nigeria is not as widespread when compared to neighbouring West African countries.

Animals↗
PubMed2005

Response of vitiligo to PUVA therapy in Saudi patients.

BACKGROUND: Vitiligo is not uncommon in southern Saudi Arabia. The response of Saudi patients to PUVA therapy has not been previously assessed. The aim of this study was to evaluate this response. METHODS: This is a retrospective study for the period of 1990-2001 in which 32 patients were included: Data were collected from the patients' records, including: age, sex, age at onset of disease, type of vitiligo, cumulative dose, maintenance dose, total number of sessions, number of sessions to induce pigmentation, treatment duration, and response rate. RESULTS: The overall response rate was 59.4%. The most sensitive sites were the face, trunk, arms, and legs, while the most resistant sites were the hands, feet, and perioroficial areas (perioral and periorbital). Acute complications occurred in 59.4%, while chronic complications occurred in 78.1%. Analysis of the factors that affect the response rate showed that age, sex, the disease duration, and the treatment duration did not affect the response rate, while the surface area and the number of sessions to induce pigmentation showed a positive relation. CONCLUSIONS: PUVA is still considered as the most appropriate and effective treatment for vitiligo. Saudi patients showed good response to treatment in general. Some sites such as the face, trunk, arms, and legs showed sensitivity to therapy, while hands, feet, and periorificial areas showed resistance to therapy. Generalized type was the best type to respond, followed by the periorificial type. Acral and segmental types were very resistant to therapy.

Adolescent↗
PubMed2004

Direct observation of high-temperature polaronic behavior in colossal magnetoresistive manganites.

The temperature dependence of the electronic and atomic structure of the colossal magnetoresistive oxides La1-xSrxMnO3 (x=0.3, 0.4) has been studied using core and valence level photoemission, x-ray absorption and emission, and extended x-ray absorption fine structure spectroscopy. A dramatic and reversible change of the electronic structure is observed on crossing the Curie temperature, including charge localization on and spin-moment increase of Mn, together with Jahn-Teller distortions, both signatures of polaron formation. Our data are also consistent with a phase-separation scenario.

Journal Article↗
PubMed2004

Information needs of Asian and White British cancer patients and their families in Leicestershire: a cross-sectional survey.

The aim of this questionnaire survey was to find the information needs of British Asian cancer patients. An additional objective was to find the extent of family involvement when the patient was given the cancer diagnosis and the patients' views about information disclosure. We interviewed 82 Asian patients and 220 random white control patients. More white British patients gave positive answers to the statement 'I want as much information as possible' than Asian patients (93.1 vs 77.5%, P<or=0.001). However, 92.6% of Asian patients wanted to know if they had cancer. Many more Asians (66.2 vs 5.1%, P<0.001) indicated the general practitioner (GP) as the preferred source of information. This may be because 56% of English-speaking Asian patients would prefer to discuss their illness in their mother tongue. In Leicester, many Asian patients have Asian GPs. The vast majority of both Asian and British patients agreed that family or friends should be present when patients are given the cancer diagnosis. However, Asians were more likely to be alone (24 vs 15%, P=0.008) when told they have had cancer. The majority of patients (both white British and Asian) want to control the disclosure of information to relatives and friends and would like to be present at doctor/family meetings.

Adolescent↗
PubMed2003

An improved morphological approach to background normalization of ECG signals.

This paper describes an improved morphological approach to remove baseline wander from neonatal electrocardiogram (ECG) signals, with particular emphasis on preserving the ST segment of the original signal. The algorithm consists of two stages of morphological processing. First, the QRS complex and impulsive noise component due to skeletal muscle contractions etc., are detected and removed from the input signal. Second, the corrected QT interval (QTc) and RR interval are used to determine a structuring element. With this structuring element, the same morphological operation as in the first stage is then applied to the QRS-removed signal to obtain and remove the baseline wander. The performance of the algorithm is evaluated with simulated and real ECGs. Compared with an existing morphological method, there is a substantial improvement, especially in reducing distortion of the baseline waveform within the PR and QT intervals.

Algorithms↗
PubMed2001

The incidence of pemphigus in the southern region of Saudi Arabia.

BACKGROUND: This is the first epidemiologic study of pemphigus in the southern region of Saudi Arabia. METHODS: Data were collected from patient records in the outpatient and inpatient departments of Asir Central Hospital during the period 1990-99. The diagnosis of pemphigus was based on the clinical, histopathologic, and direct immunofluorescence patterns which were consistent with pemphigus. RESULTS: The results showed that the mean incidence of the disease in the general population was 0.16/100 000; the mean incidence of the disease in the population above 20 years of age was 0.27/100 000. The prevalence of the disease at the end of the study period was 1.56/100 000 for the total population, and 2.7/100 000 for the population above 20 years of age. The male to female ratio was 2.2 : 1. The age of onset of the disease ranged from 23 to 67 years, except for one case at an age of 9 years, giving an average of 43.1 +/- 13.4 years and a median of 40 years. Pemphigus vulgaris was the most commonly encountered type, followed by pemphigus erythematosus (94.7% and 5.3%, respectively). Mucosal involvement occurred in 84.2% of cases. No association with neoplasia was found in the current study. CONCLUSIONS: Pemphigus in the southern region of Saudi Arabia is as common as in other parts of the world, but with higher mucosal involvement.

Adult↗
PubMed2000

Ocular findings in aplastic anemia.

OBJECTIVE: To analyze the ocular findings in aplastic anemia. DESIGN: Eighteen patients with aplastic anemia were examined. RESULTS: Ocular findings included cotton wool spots (38%), nerve fiber layer or preretinal hemorrhages (67%), vitreous hemorrhages (13%), a picture resembling central retinal vein occlusion (13%) and optic disk edema (6%). Preretinal hemorrhages were the presenting sign of aplastic anemia in 2 patients (13%). CONCLUSIONS: A blood profile is needed in patients with unexplained retinal hemorrhages. Patients with aplastic anemia need to avoid ocular massage and Valsalva maneuvers to decrease ocular morbidity.

Adolescent↗
PubMed1998

The relationship between serum levels of erythropoietin (EPO) and insulin-like growth factor-1 (ILGF-1) and hematocrit (HCT) in breast cancer patients receiving non-nephrotoxic chemotherapy.

OBJECTIVE: To evaluate the relationship between the hematocrit (HCT), serum erythropoietin (EPO) and insulin-like growth factor-1 (ILGF-1) levels in breast cancer patients receiving non-nephrotoxic chemotherapy. METHODS: Seventeen patients with stage II breast cancer were included. All received 6 cycles of non-nephrotoxic chemotherapy (cyclophosphamide, 5-fluorouracil and doxorubicin or methotrexate with or without tamoxifen). Insulin-like growth factor-1 and EPO levels were determined before and at the end of therapy. Serum EPO levels were determined by Enzyme linked- immunosorbant assay (ELISA) while those of ILGF- I by radioimmunoassay (RIA). RESULTS: A significant drop in mean HCT from 37.41%+/-0.77% to 35.18%+/-0.70%, associated with a significant decline in ILGF-1 levels from 92.1+/-15.48 ng/ml to 52.75+/-10.5 ng/ml at the end of the treatment was noted. This association became significant when patients receiving tamoxifen were excluded (r=0.69, p=0.02). The mean serum EPO levels increased significantly from 13.64+/-0.55 U/l to 19.44+/-3.18 U/l and correlated negatively with ILGF-1 level (r=-0.46, p=0.05). There was no significant relation between the serum EPO levels and HCT (r=-0.26, p=0.32). CONCLUSION: The current data show that ILGF-1 may play an important role in erythropoiesis and it correlates better than EPO with HCT in breast cancer patients receiving non-nephrotoxic chemotherapy.

Adenocarcinoma↗
PubMed1997

Photodynamic destruction of Haemophilus parainfluenzae by endogenously produced porphyrins.

Bacterial resistance against antibiotic treatment is becoming an increasing problem in medicine. Therefore methods to destroy microorganisms by other means are being investigated, one of which is photodynamic therapy (PDT). It has already been shown that a variety of Gram-positive and Gram-negative bacteria can be killed in vitro by PDT using exogenous sensitizers. An alternative method of photosensitizing cells is to stimulate the production of endogenous sensitizers. The purpose of this study was to investigate the bactericidal efficacy of PDT for Haemophilus parainfluenzae with endogenously produced porphyrins, synthesized in the presence of delta-aminolaevulinic acid (delta-ALA). H. parainfluenzae incubated with increasing amounts of delta-ALA showed decreased survival after illumination with 630 nm light. No photodynamic effect on the bacterial viability was found when H. parainfluenzae was grown without added delta-ALA. H. influenzae, grown in the presence of delta-ALA, but not capable of synthesizing porphyrins from delta-ALA, was not affected by PDT. Of the range of incident wavelengths, 617 nm appeared to be the most efficient in killing the bacteria. Spectrophotometry of the bacterial porphyrins demonstrated that the maximum fluorescence occurred at approximately 617 nm, with a much lower peak around 680 nm. We conclude that a substantial killing of H. parainfluenzae by PDT in vitro after endogenous sensitization with delta-ALA can be achieved.

Aminolevulinic Acid↗
PubMed1997

Terbinafine in the treatment of cutaneous leishmaniasis: a pilot study.

Twenty-seven patients were randomly picked for an open pilot study using terbinafine with a dose range of 250-500 mg/day for 4 weeks. The inclusion criteria were as follows: (1) the patient had to be aged 5 years or older; (2) the patient could be of either sex; (3) any number or location of the lesions was allowed; (4) parasitologic confirmation was required; (5) the patient was allowed no previous treatment; (6) pregnant or lactating patients were excluded; (7) informed consent from the patient or his/her parents was required. The parasitologic diagnosis was carried out by a slit smear technique followed by a Giemsa stain for parasite identification. Terbinafine was given in two different doses to two groups sorted according to age. The groups were as follows: Group 1, 5-15 years, 125 mg orally twice daily for 4 weeks: Group 2, > 15 years, 250 mg orally twice daily for 4 weeks. Laboratory blood investigations including complete blood count, creatinine, urea, and liver function tests were carried out initially and at 2 weeks and 4 weeks. Clinical response was evaluated by assessing the per cent of improvement of erythema, induration, and ulceration at 2 weeks and at 4 weeks after admission. The final assessment was reported at 4 weeks: complete cure, 100% improvement with no relapse; partial cure, > or = 60% improvement; failure, < 60% improvement. Overall clinical response included patients with both complete and partial cure. Follow-up for patients with complete cure was carried out monthly for 6 months to assess the relapse rate. Patients with partial cure or failure were switched to sodium stibogluconate intralesionally.

Administration, Oral↗
PubMed1997

A case of angiolymphoid hyperplasia with eosinophils.

The authors report a case of angiolymphoid hyperplasia with eosinophils in a 45-year-old Syrian man working in Saudi Arabia. His skin lesions recurred eighteen months after they were surgically excised.

Angiolymphoid Hyperplasia with Eosinophilia↗
PubMed1996

Geometric analysis of coronal decompensation in idiopathic scoliosis.

STUDY DESIGN: Frontal plane geometry of postoperative curves was analyzed using a geometric model to investigate the relationship between coronal decompensation and postoperative apical shifts from the center sacral line for various thoracic and lumbar Cobb angles. OBJECTIVE: To determine if a balanced spinal configuration is possible when the postoperative lumbar curve is larger than the thoracic curve, and to determine the limits on the postoperative magnitude of the lumbar curve relative to the thoracic curve beyond which a spinal configuration with acceptable balance cannot be achieved. SUMMARY OF BACKGROUND DATA: Previous studies have suggested that overcorrection of the primary thoracic curve may be the principal cause of coronal decompensation after selective thoracic correction and fusion in King Type II curves. Also, other causative factors, such as inappropriate selection of fusion levels and hook patterns, have been implicated as possible reasons for decompensation after Cotrel-Dubousset instrumentation for idiopathic scoliosis. METHODS: Postoperative thoracic curves of 20 degrees, 25 degrees, and 30 degrees were simulated on a model spine. For each thoracic Cobb angle, three left lumbar curves were simulated with the lumbar curve larger than thoracic by 5 degrees, 10 degrees, and 15 degrees. For each combination of thoracic and lumbar Cobb angles, spinal configurations corresponding to different lateral shifts of the thoracic and lumbar apical vertebrae from the center sacral line were obtained. RESULTS: For a given combination of postoperative thoracic and lumbar Cobb angles, there is an optimal range of postoperative lateral distance between the thoracic and lumbar apices (relative apical distance) that will maintain acceptable balance (decompensation < or = 10 mm). Smaller values of the relative apical distance will decompensate the spine. For a constant postoperative thoracic Cobb angle, the postoperative distance between the thoracic and lumbar apices needed to maintain a balanced spine increases with increasing postoperative lumbar Cobb angle. Similarly, for a constant difference between the postoperative thoracic and lumbar Cobb angles, the postoperative distance between the thoracic and lumbar apices needed to maintain a balance spine increases with increasing postoperative thoracic Cobb angle. For postoperative thoracic curves of 20 degrees-30 degrees, acceptable balance can be achieved when the magnitude of the postoperative lumbar curve is up to twice the thoracic curve as long as adequate postoperative relative apical distance can be maintained. CONCLUSIONS: Decompensation does not appear to be caused by the relative magnitudes of the postoperative thoracic and lumbar curves, but is a result of inadequate relative distance between the thoracic and lumbar apical vertebrae in the postoperative geometry.

Humans↗
PubMed1996

Cutaneous leishmaniasis: schedules for intralesional treatment with sodium stibogluconate.

BACKGROUND: Various therapeutic modalities have been used for treating cutaneous leishmaniasis. Intralesional pentavalent antimonial injection is one of the effective therapeutic modalities. In this study, the efficacy of three different intralesional schedules with sodium stibogluconate have been investigated. METHODS: Ninety-six patients with 129 lesions were entered into the study, all with confirmed diagnosis of cutaneous leishmaniasis. The lesions were treated with three different schedules, including daily, alternate day, and weekly interlesional injections of sodium stibogluconate. The clinical response was then compared to arrive at the most effective schedule. RESULTS: The clinical responses (complete and partial cure) were 67%, 97%, and 91% for the daily, alternate-day, and weekly schedules, respectively. Lesions with either partial cure or failure of treatment were injected weekly with the same medication until complete cure had been achieved. The final overall success rate of complete cure was 99.2%. CONCLUSIONS: Alternate day or weekly intralesional treatment of cutaneous leishmaniasis with sodium stibogluconate are more effective than daily treatments.

Adolescent↗
PubMed1995

Skin necrosis following subcutaneous heparin injection.

Heparin-induced skin necrosis is a rare but serious complication of subcutaneously administered heparin. Previous reports indicate that the skin necrosis is often accompanied by thrombocytopenia and occasionally by lethal thromboembolism. It thus shows features similar to the heparin-induced thrombocytopenia (HIT) syndrome and probably represents a localized form of this condition. Caution is required in the event of skin necrosis; heparin therapy should be ceased immediately and not used again if the complications of HIT are to be avoided.

Aged↗
PubMed1995

Psychiatric day centres--the Singapore experience.

Psychiatric Day Centres are an important aspect of psychiatric community services and care. In Singapore we have developed our Day Centres with the needs of our own patients in mind. At present there are four Psychiatric Day Centres and they focus on vocational and psychosocial rehabilitation. A wide range of structured activities are provided at each of the Day Centres and the programmes are individualised as far as possible to meet the needs of each patient. A multidisciplinary team looks after each patient. This paper outlines the historical aspects of Psychiatric Day Centres and highlights the objectives of the Day Centres administered by Woodbridge Hospital. Patients are grouped into three categories according to their occupational and social skills; programmes and care are provided according to their needs. Of the one hundred and eighty attenders, the sex distribution is almost equal and they are mainly in the twenty to forty-nine age group. Schizophrenia is the most common illness among the attenders and the majority are in the Sheltered Work Group. More than half of them had attended a Day Centre for between one to two years and less than a third had recent admissions to hospital.

Adult↗